Graphite sheet materials can be used for distributing heat generated at a heat source. A heat spreader formed of sheets of graphite material can take advantage of the anisotropic thermal properties of graphite, In particular, graphite sheet material exhibits a high thermal conductivity in the plane (x,y) of the graphite sheet and a much lower thermal conductivity through the thickness (z) of the graphite sheet. More specifically, the graphite sheet can have a thermal conductivity ranging from about 1200-1500 W/m-K (depending upon the thickness) in a direction that is generally parallel to the layer planes (x,y) and from 3-10 W/m-K perpendicular to the layer planes (z). In this way, the graphite sheet can function as both a heat spreader and an insulator.